There are only five maize samples present that the nos could not be detected parallel to the CaMV 35S and the result could not be confirmed with another test. However, because these samples are maize flour and canned maize they are very unlikely to be contaminated cauliflower mosaic virus. According to many other researchers, further explanation for the presence of the CaMV 35 S alone is that the detection of the nos terminator is less sensitive than that of the 35 S promoter (Cardarelli et al., 2005; Lipp, Brodmann, et al., 1999; Ujhelyi et al., 2008). In our study, positive amplification of RUR soy in six nos negative samples supported this finding. In case of maize it could also be related to the lack of the nos terminator which is common for several maize events.